1. Field of the Invention
The present invention relates to an image sensing apparatus and an image stabilization method, and more particularly, to a technology that achieves smooth image stabilization control in an image sensing apparatus that has an image stabilization function that optically corrects camera shake of an image sensing apparatus such as a camera.
2. Description of the Related Art
In optical correction algorithms for related-art optical image sensing apparatuses equipped with an optical image stabilization mechanism, there is a control method involving associating two correction axes. However, if each of the two orthogonal correction axes is allowed to acquire its correction maximum value, the lens barrel becomes unacceptably large and optical aberration occurs. To solve these problems, providing a control unit so that the optical camera shake correction maximum allowed driving range is controlled and controlling the movable range of the correction optical system has been proposed (as seen in, for example, Japanese Patent No. 3162126).
However, in the above-described related art example, in the movable range within the optical image stabilization correction maximum allowed driving range, although the two correction axes of the image stabilization optical system can be freely driven without limitation, once the correction maximum allowed driving range is achieved the image stabilization optical system movement stops. As a result, problems such as the following occur.
That is, depending on whether inside or outside the correction maximum allowed driving range, the region through which the image stabilization optical system can freely move and the region in which it stops are separate. As a result, although a sufficient suppression effect can be obtained in a case in which a camera shake amount is applied that is within the movable range up to the correction maximum allowed driving range, when a camera shake amount is applied that exceeds the correction maximum allowed driving range the image stabilization stops at the point at which the correction maximum allowed driving range is reached. As a result, image stabilization continuity is suddenly lost, leading to states (images) in which camera shake is corrected and states (images) in which camera shake is not corrected.
With video cameras in particular, which sense images continuously, from the viewpoint of image stability the viewer may be made to feel uncomfortable or even unpleasant if correction continuity is not maintained.